Alcohol

What happens in the kidneys?

The molecules and metabolites of alcohol arrive at the filter elements of the kidneys, the nephrons.

The alcohol and metabolites flow with the blood fluid, or plasma, through the filters (1) and become part of the primary urine. The largest part of the primary urine is then returned to the blood, including the alcohol molecules that are not yet broken down (2). The breakdown products (metabolites) stay behind in the primary urine. They are eventually discharged from the body in the final urine (3).

The speed at which alcohol is eliminated from the body approximately equals the speed at which the liver can convert the alcohol into metabolites. A small percentage of alcohol is discharged through the lungs and exhaled. We can smell this on the breath of heavy drinkers. It can also be measured by a breathalyser test to indicate the concentration of alcohol in the blood.